ML20236W870

Criticality Safety Evaluation License Annex Integral Fuel Burnable Absorber Fuel Rod Mfg

ML20236W870
Person / Time
Site:	Westinghouse
Issue date:	07/31/1998
From:	WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
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ML20236W864	List: ML20236W870
References
NUDOCS 9808060266
Download: ML20236W870 (23)

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{{#Wiki_filter:_ _, _ _ _ _ _ _ _. -, _ _ _ _ _,, _,., _, - _. _,,, - _ _,, _ _ _ _., CSE LICENSE ANNEX IFBA FUEL ROD MANUFACTURING l l l 9808060266 980731 {DR ADOCK 07001151 PDR

CSE LICENSE ANNEX l l IFBA FUEL ROD MANUFACTURING \\ l ( TABLE OF CONTENTS TA BLE OF CONTENTS....... .................. I REV1S10NRECORD. .II PROCESS SUM MA R7. ..... I ASSEMBLE iUEL NOD COMPONENTS _ ._1 LOAD PELLETCAtdETTES =l FUEL ROD FABRICATION - .2 IFDA FUEL ROD SCRAP / REWORK AREA - -3 MANUFACTURING OPERATING PROCEDURES.. 4 ENVIRONMENTAL PROTECTION AND RADIATION SAFETY CONTROLS..... ... 5 NUCLEAR CRITICA LITY SAFETY (NCS) CONTROLS AND FAULT TREES... 5 CHEMICAL SAFETY AND FIRE SAFETY CONTROLS.. ....-.... 23 1 l i i 1 1 ) Initial Issue Date: 31 JUL 98 Page No. i Revision Date: Revision No. _0

GSE LICENSE ANNEX 1 IFBA FUEL ROD MANUFACTURING REVISION RECORD REVISION DATE OF PAGES REVISION NUMBER REVISION REVISED RECORD l Initial Issue Da:e: 31 JUL 98 Page No. ii Revision Date: Revision No. _0 L_______________-______________________.-------.------

CSE LICENSE ANNEX IFBA FUEL ROD MANUFACTURING Process Summary The scope of this document includes the process description of the systems and components used to fabricate nuclear fuel rods in the IFBA Fuel Rod Manufacturing Area of the Columbia Plant. The IFBA Fuel Rod Manufacturing Area involves the following areas: The assembly of fuel rod components. j The building of the pellet stacks for fuel rod loading. l e-The drying of pellets for removing potential hydrogen contamination. The fabrication of fuel rods in the moisture controlled glovebox. The inspection of the fuel rods by the passive scanner. The transporting of fuel rods to the QC Inspection Area. The scrapping and/or rework of fuel rods. e Also included are the controls and features of the systems and stmetures that may affect l criticality safety analyses and evaluations. Excluded from the scope of this criticality safety evaluation are the following: ADU fuel rod fabrication and QC Inspection Area (included in the CSE for ADU fuel rods). l Fuel Assembliec in.-hipping containers (part of separate shipping container license). Tube fabrication and component cleaning. Final assembly (included in the CSE for Final Assembly Area). The ZrB coating of enriched pellets (included in the IFBA Process Area). l 2 The recycling of pellets (included in the IFBA Process Area). ASSEMBLE FUEL ROD COMPONENTS i Tubing which has been marked with a bar-code, bottom plugged and welded, and inspected is picked up from the tube fabrication lines. Cleaned and released top end fuel rod plags, fuel rod springs or other mechanical components, as applicable, are picked up from the Component Cleaning Area. l LOAD PELLET CASSETTES l Initial Issue Date: 31 JUL 98 Page No. 1 Revision Date: Revision No. _0 [ w___-_____-_______-________.

Coated enriched and/or uncoated enriched, and/or blanket pellets are staged in carts at one or both of the manual collating stat.ans. The pellet stacks (25) are measured and loaded into capture row trays and assembled in a cassette. Approximately 10 capture row trays are used in each cassette. The completed cassette is staged at one of two vacuum drying ovens for removal of any possible hydrogen contamination. VACUUM DRYING OFPELLET CASSETTES When four (4) cassettes are built and staged at one of the two vacuum drying ovens, the - cassettes are loaded into the oven for drying. A three-minute leak check is done on the oven chamber to verify that an acceptable vacuum can be maintained. Process samples are evaluated for oxygen contamination and l'ydrogen content after completion of the oven cycle. The dried cassettes are unloaded into an atmosphere controlled glovebox and then transferred to the rod loading portion of the glovebox. FUEL ROD FABRICATION After vacuum drying, the cassettes are unloaded into a dry air atmosphere controlled glovebox where the moisture is maintained at less than 100 PPM moisture. Cassettes are received at the pellet loading station after vacuum drying. Tubing is placed at the loading station and positioned for pellet loading. Each tray in the cassette is removed and the pellets are raked onto a vibrating loader where they are introduced into the fuel tube. Pellets that are seen to be damaged prior to loading are removed from the tray and placed in either a scrap chute, or on the station floor. The pellets are removed from the chute and station floor prior to the annual SNM physical inventory. 'After pellet loading is completed, the loaded fuel rods are introduced into the main glovebox area where the bar-code is read and the rods are assigned to a cassette. A dimensional check of the plenum area is done where the pellet stack can be adjusted using filler pellets. The filler peliets are contained in a bowl at the check station. At the next station, the end of the tube is cleaned to remove any pellet dust from loading. A spring or other mechanical component is inserted in the fuel rod to prevent the pellet ( stack from shining. The fuel rod is closed by inserting a top end plug into the open end of the tube. The completed fuel rod is then transferred from the glovebox to the weld line. At the weld line the fuel rod receives a top girth weld. The fuel rod is then weighed prior to the seal weld station. At the seal weld station the fuel rod is pressurized with helium and then seal welded. The fuel rod is then transferred to the passive gamma scanner 70 verify the enrichments in the pellet stack. After completion of the gamma scan inspection, the fuel rod is transferred to the loading dock before being transported to the QC Inspection Area. TRANSPORTRODS TO QCINSPECTION AREA ( Initial Issue Date: 31 JUL 98 Page No. 2 Revision Date: Revision No. _0

The completed fuel rods are loaded into caskets at the off load station. The fuel rods are arranged in the casket in layers of twenty-five with half inc5 nylon spacers between each layer. A maximum of five layers (125 rods) are placed mto one casket. When the casket is closed and sealed, it is moved to a conveyor using an overhead crane. The honveyor transports the caskets to a fork truck where they will be transported to the QC Inspection Area. Only two caskets may be transported at one time on the fork truck. QCINSPECTION AREA - At the QC Inspection Area, completed fuel rods are staged at the fuel rod weigh scales. The fuel rods are individually weighed and then transferred to the leak detector in groups of twenty-five where the hermeticity of the rods is checked. After the leak check is completed, the fuel rods are transferred to either ultrasonic or x-ray inspection devices where the welds are inspected for in:ernal integrity. The fuel rods are then positioned at the active gamma scanner where automatic inspections are made for the pellet stack length, enrichment, pellet gaps, and the presence of a spring / retaining device. After active gamma scan the fuel rods are placed into small channels and staged at the Dimensional and Visual (D & V) Area. The fuel rod length and appearance are inspected at D & V anxi released fuel rods are placed into large channels for use in the Final Assembly Area. IFBA FUEL ROD SCRAP / REWORK AREA 1 Fuel rods that are not needed for the fuel region for which they are built, or that do not meet drawing or inspection limits, are held for rework or scrapping. The top end plug is removed using a lathe and the tube end is faced. If the fuel rod is to be scrapped, it is taken to the pellet dump hood where pellets are dumped into an approved scrap container. The pellet dump hood is connected to the exhaust system to prevent any airborne contamination. The emptied tube is cut into secdons 'using a tubing cutter and held for recycling. When the approved scrap container is full, the container is scaled and transferred to the Scrap Recycling Area. Fuel rods designated for rework are reworked using approved procedures. When the rework operation is completed, a new top end plug is put onto the tube in place of the old one. The reworked fuel rod is transferred to the weld line to complete its j fabrication. After fabrication is complete, the reworked fuel rod is processed using normal operating procedures. t-Initial Issue Date: 31 JUL 98 Page No. 3 i' Revision Date: Revision No. _0

MANUFACTURING OPERATING PROCEDURES l TDOCUMENTl'- o Y ,'W vDOCUMENT TITLE ' JNUMBER3' 'O MOP-%1002 Receive And Segregate Defective IFBA Fuel Rods MOP-%1009 Fuel Rod Handling - IFBA l MOP-%1015 Rams Instructions For IFBA Fuel Rod Area MOP-%1020 Reweld Roda To Remove Girth Weld Defects-IFBA MOP-%1040 Imad Fuel Rods -- IFBA MOP-%1050 Plug Fuel Rods - IFBA MOP-%1055 Girth Weld Fuel Rods MOP-%1060 Automatic Seal Welding Of IFBA Fuel Rod End Plugs MOP-%1080 Remove Top End Plug -- IFBA MOP-%1090 Regage Rods After Top End Rework -- IFBA MOP-%1095 Polish Small Visual Defects On Fuel Rods -- IFB A MOP-961100 Depressurize Fuel Rods -- IFBA MOP-%1105 Control Of Scrap IFBA Rods MOP-%I115 Automatic Tube End Cleaning Of IFBA Fuel Rods MOP-961120 General Operating Procedure - IFBA Rod Area MOP-961130 Prepare Process Control Samples - IFBA MOP-%1135 Weigh And Tamper-Seal Fuel Rods -- IFBA MOP-%1165 Instructions For IFBA Rod Staging Area MOP-%1175 Automatic Plenum Gaging - IFBA MOP-%1180 Ataomatic Spring Insertion -- IFBA MOP-%1200 Fuel Rod Weighing Procedure IFBA MOP-%1205 Abrade Oversi ' Weld 7 Or Cocked End Plugs - IFBA MOP-961210 Scrap IFBA idods And Recover Pellets MOP-%1240 Disposition Of Rejected IFBA Rods MOP-%1245 Receive IFBA Fuel Rod Components ~ MOP-%1255 IFBA Passive Gamma Scanning Unit MOP-%1260 Soft Rod Handling At Passive Gamma Scanner MOP-%2040 IFBA Glove Box Window Replacement MOP-%2050 IFBA Glove Box Glove Replacement MOP-%2060 Glove Box And Atmosphere Control System MOP-%2070 Glove Box Startup MOP-962080 Operate Cassette Tunnel Conveyor System MOP-%2090 Regenerate Glove Box Atmosphere System Drvers MOP-%2100 Breachlag Of Glove Box For Maintenance MOP-963010 Operation Of The IFBA Vacuum Redry Oven MOP-%3040 Redry Oven Cleaning MOP-964016 Manual Collator-Operation Procedure -- IFBA MOP 964020 Manual Collator Aborted Run Recovery - IFBA MOP-964030 Collator Scale Check - IFBA MOP-964050 Reweigh IFBA Bottcm End Preplugged/Prewelded Fuel Tube MOP-964060 Adjust IFBA Pellet Stack length MOP-964070 IFBA Rod Area Setup MOP-964074 IFBA Rod Area - Tooling Control System COP-871090 Enrichment Or Pellet Size Cleanout Of IFBA Facility j COP-871160 Package IFBA Rods For Transport l l l Initial Issue Date: 31 JUL 98 Page No. 4 l Revision Date: Revision No. _0 I l

Environmental Protection and Radiation Safety Controls To be provided in a future Integrated Safety Assessment ) Nuclear Criticality Safety (NCS) Controls and Fault Trees The scope of this document includes. 3 Loading of pellet cassettes Vacuum drying of pellets and fabrication of IFBA fuel rods j e Transport ofIFBA fuel rods to QC Inspection Area e QC Inspection Area l Scrap / rework ofIFBA fuel rods e This CSE for fabrication of IFBA Rods compriscs the criticality safety evaluations for the IFBA l Fuel Rod Manufacturing Area Excluded from the scope of this CSE are: ) Absorber coating and inspection of pellets Movement of pellet carts to the manual collating stations Storage and final assembly of inspected IFBA fuel rods i e Pellets removed from scrap / rework fuel rods in scrap / rework hoods in the IFBA Fuel Rod e Area l l Load Pellet Cassettes Controls Safety Significant Controls Passive Engineered Controls (PEC) a) The roof, overhead pipes, etc., provide integrity to prevent sources of moderator. IE-2. Periodic verification is !pt needed because any leaks are readily detected and corrected during normal process operations. Active Engineered Controls (AEC) - None I i Administrative Controls with Computer and/or alarm assist - None t Initial Issue Date: 31 JUL 98 Page No. 5 l Revision Date: Revision No. _0 f L_____._.___

Administrative Controls (AC) a) The pellet and cassette trays are designed to hold 25 stacks of pellets in a one-high arrangement (no, stacking). IE-1. Periodic verification is not needed because of operator training and work prac'tice. b) Water as a fire suppressant is used as a spray or mist. IE-10. Periodic training of personnel in area is required. Margin of Safety The nuclear criticality margin of safety is not only adequR but also quite large, because the 4 Bounding Conditions are much more reactive than conditions expected for normal and expected or credible upset conditions. Calculations in the referenced evaluations assume optimum moderation and full water reflection. The calculations indicate that k,for the normal and expected upset conditions will not exceed 0.95. No credible upset will cause k,, to > 1.0. The parameters that affect neutron multiplication, gi'en the bounding assumptions, are geometry and moderation. The controls on these parameters are both engineered and administrative in nature. Criticality would only be possible if pellets were placed in a large container of water or other moderator. Because such containers are not available in the IFBA Area and because moderator sources and volumes are normally limited, such a scenario is not credible. The double contingency principle has been satisfied. Summary OfInitiating Events Which lead To Credible Process Upsets No credible initiating events have been identified for ADU fuel rod loading and end plug welding that could lead to a criticality (k, = 1.0). For moderation control, the plane of the safe slab is well above the floor so that flooding is not credible. Accidental (roof leaks) or deliberate (fire suppression) sources of moderator would be low-density materials so that optimum moderation is not likely. For geometry control, credible process upsets would not violate the safe slab limit. The safe volume control.:n stack pellets and scrap pellets is subject to configuration control. Dropped pellets, if any, would assume a safe slab configuration. The fault tree Figure 6.3-1 (pellets) considers certain potential initiating events, none of wish lead to criticality. These initiating events are discussed herein to demonstrate that they axe very unlikely. IE-1. Pellet and cassette trays are intended to hold pellets in a one-high planar array. Without sides, stacking of pellets would be quite limited. Likewise, retention of liquid moderator would be quite limited. initial Issue Date: _ 31 JUL 98 Page No. 6 Revision Date: Revision No. _0 1 t___--- a

e IE-2. Tae roof, overhead pipes, etc., provide integrity to prevent sources of moderator. Even if the integrity were lost, the moderator would affect only a small portion of the infinite slab. The, slabs do not have the capability to hold a large quantity of moderator so that the moderating effect of inadvertent moderator would be quite small. IE-3, IE-4 & IE 5. Deleted IE-6, IE-7 & IE-8. Not applicable e e. IE-9. Deleted IE-10. Use of water as a fire suppressant is limited to sprays or mists. This will provide a low density moderator over a small area of an infinite slab array, producing a small moderating . effect on the assumed infinite slab. IE-11. Administrative controls on nonfavorable geometry containers prevent the collection of pellets in nonfavorable (NFG) geometry containers. Process equipment is not capable of collecting large quantities of moderator. Movable NFG containers are not permitted in the area per COP-843002 and sketch 843002-3. Note: IE-11 was deleted from the fault tree because it is outside the scope if this CSE. IE-12 though IE-17. Not applicable IE-18. Moderator for process operations (oils, solvents, mop water, etc.) is brought into the area in favorable volume or favorable geometry comainers. IE-19. Good housekeeping prevents unwanted secumulations of pellets / rods to >4.5" depth. j It also provides identification of SNM, minimizes combustibles and hence the possibility of j introducing fire suppression water (moderator), and allows space to correctly space favorable i geometry containers. I Summary Tables - See Tr.bles 5.3-1 and 5.3-4. Vacuum Drying Pellet Cassettes, Rod Loading, Rod Welding, And Gamma Scanning Controls . Safety Significant Controls Passive Engineered Controls (PEC) Passive engineered controls are described ir. the License SNM-1107 and in RA-108. The requirements for functional verification are determined in this section. l Initial Issue Date: 31 JUL 98 Page No. 7 Revision Date: Revision No. _0

a) The roof, overhead pipes, etc., provide integrity to prevent sotrees of moderator. IE-2. Periodic verification is g needed because any leaks are readily detected and corrected during normal process operations. b) Gloveboxes provide a barrier to inadvertent additions of moderator. IE-6. Periodic verification of integritv of glovebox is not needed. Leaks are readily detectable by instruments that inonitor glovebox atmosphere. c) Gloveboxes and conveyors provide a plane for the safe slab of pellets and rods. IE-7. Periodic verification of glovebox integrity is g needed because of continuous surveillance during normal operations. d) Channels and channel carts provide geometry control. IE-8. Periodic verification is no_t needed. As-built verification before new channels and carts are placed into service is accomplished by configuration control. Active Engineered Controls (AEC)- None Administrative controls with Computer and/or Alarm Assist - None Admimstrative Controls (AC) a) Stacking of pellet trays 7ceeding 4.5" depth of ellets. IE-1. No stacking of trays is allowed. t b) Water as a fire suppre sant is used as a spray or mist. IE-10. Periodic training of personnel in area is required. c) Scrap pellet cleanout is performed annually. IE-12. Periodic verification is accomplished by the annual cleanout for SNM physical inventory. Margiu Of Safety The margin of safety is not only adequate, but also quite large, because the Bounding Conditions are much more reactive than conditions expected for normal and expected, or credible upset conditions. Calculations assume optimum mcderation and full water reflection. The calculations indicate that k,for the normal and expected upset conditions will not exceed 0.95. No credible upset will cause k, to,> 1.0. The nuclear criticality safety basis is geometry and moderation. Because moderation may be difficult to control in an upset condition, full reflection was assumed as o Bounding Corxiition. Criticality would be possible if pellets or fuel rods were stacked to a depte exceeding 4.5" AND the fuel were immersed in water. For pellets in captured row trays in casettes, criticality was judged not credible for the following reasons: The captured row trays cannot hold water. For each row of pellets, there is a longitudinal slit or opening under the pellet stack for the entire length of the tray, and the ends of the tray are l-open. The cassette cart ins no sides - it is just an open framework into which the trays are slid. The cassette sits on the cart, and the top of the cart is approx. 28" off the floor. Initial Issue Date: 31 JUL 98 Page No. 8 Revision Date: Revision No. _0

l The double contingency principle has been satisfied. L Summary Of Initiating Events Which 12ad To Credible Process Upsets l No credible initiating evsents have been identified for ADU fuel rod loading and end plug welding that could lead to a criticality (k, = 1.0). For moderation control, the plane of the safe slab is well above the floor so that flooding is not credible. Accidental (roof leaks) or deliberate (fire suppression) sources of moderator would be low-density materials so that optimum moderation is not credible. For geometry control, credible process upsets would not violate the safe slab limit. The safe volume control on stack pellets and scrap pellets is subject to configuration control. Dropped pellets, if any, will assume a safe slab configuration. t-The fault trees Figures 6.3-1 (pellets) and 6.3-2 (rods) consider certain potential initiating events, none of which lead to criticality. These initiating events are discussed herein to demonstrate that they are very unlikely. I IE-1. Not applicable e

• IE-2.. The roof, overhead pipes, etc., provide integrity to prevent sources of moderator.

Even if the integrity were lost, the moderator would affect only a small portion of the infinite slab. The slabs do not have the capability to hold a large quantity of moderator so that the { moderating effect of inadvertent moderator would be quite small, j IE-3, E-4 & IE-5. Deleted e-IE-6. The drying oven, when closed for the drying cycle, and the gloveboxes provide a barrier against the inadvertent introduction of moderator. Moderator, as needed by operations, may - be in the glovebox so that the glovebox is not an absolute barrier against the introduction of moderator. Fire could also destroy the integrity of the barrier. 4 IE-7, The glovebox rollers and connected conveyors forra a plane for the safe slab geometry for processing rods. IE-8. The fuel rod channels provide a favorable geom:try container for fuel rods. Loss of i e l spacing or maintenance of a common plane for the channels would lead to loss of geometry. d I e IE-9. Deleted t i IE-10. Use of water as a fire suppressant is lim ted to sprays or mists. This will provide a low e density moderator over a small area of an infinite slab array, producing a small moderating effect on the assumed infinite slab. Initial Issue Date: 31 JUL 98 Page No. 9 Revision Date: Revision No. _0 i L _ -- _ -_-_--_ ___-----.-_---.------_-_- J

IE-11. Administrative controls on nonfavorable geometry containers prevent the collection of o pellets or fuel rods in nonfavorable geometry containers Process equipment is not capable of collecting large quantities of moderator. Movable NFG containers are not permitted in the area per COP-843002 and sketch 843002-3. Note: IE-11 was deleted from the fault tree because it is outside the scope if this CSE. IE-12. Pellet cleanout is performed annually. Even if the pellet height exceeded the safe slab height, the area of the slab would be small and moderator would also be necessary for criticality. The number of scrap pellets is normally quite small because the pellets are inspected before entry into the glovebox. Note: this IE replaces IE-19 for this system. IE-13 through IE-17. Not applicable IE-18. Moderator for process operations (oils, solvents, mop water, etc.) is brought into the e area in favorable volume or favorable geometry containers, IE-19. Good housekeeping prevents unwanted accumulations of pellets / rods to >4.5" depth. e It also provides identification of SNM, minimizes combustibles and hence the possibility of introducing fire suppression water (moderator), and allows room to correctly space favorable geometry containers. Common Mode Failure No common mode failures were identified. Summary Tables - See Tables 5.3-2 and 5.3-4. Transport Rods To QC Inspection Area Controls Safety Significant Controls Passive Engineered Controls (PEC) a) The roof, overhead pipes, etc., provide integrity to prevent sources of moderator. IE-2. Periodic verification is no_t needed because any leaks are readily detected and corrected during cormal process operatiors. Active Engineered Controls (AEC) - None Administrative Controls with Computer and/or Alarm Assist - None Administrative Controls (AC) InitialIssue Date: 31 JUL 98 Page No. 10 l Revision Date: Revision No. _0 E_ .]

a) Water as a fire suppressant is used as a spray or mist. IE-10. Periodic training of pctsonnel in I area is required. b) Fuel rods are limited to maximum one-high on nylon carrier (25 rods). IE-14. Continuous, periodic performance verification is required by operators and supervision. c) Caskets are limited to five nylon carriers. maximum, per casket. IE-15. Continuous, periodic performance verification is required by operators and supervision. d) Loaded caskets must be closed and must not be stacked. IE-16. Continuous, periodic performance verification is required by operators and supervision. e) Two caskets, ma hnum, per in transport. IE-17. Continuous, periodic performance verification is required by operators and supervision. Margin of Safety The margin of safety is adequate, and also quite large, because the Bounding Conditions are much more reactive than conditions expected for normal, and aspected or credible upset conditions. Calculations assume full interstitial moderation and full water reflection. The calculations indicate that k,,for the normal and expected upset conditions will ne exceed 0.95. No credible upset will cause k,, to j>_,1.0. The parameters that directly affect neutron multiplication are geometry and moderation. Because moderators do not normally exist, but are not absolutely controlled, geometry is used as a control. These controls have high reliability. Criticality is found to be unlikely. Criticality would be possible if geometry controls were lost and moderator were added in large quantities. No upset condition has been identified that would cause these two upsets simultaneously. The double contingency principle has been satisfied. i Summary OfInitiating Events that I.ead to Credible Process Upsets No credible initiating events have been identified for ADU fuel rod loading and end plug welding that could lead to a criticality (k,, = 1.0). For moderation control, the plane of the safe slab is well above the floor so that flooding is not credible. Accidental (roof leaks) or deliberate (fire suppression) sources of moderator would be low density materials so that optimum moderation is not credible. For geometry control, credible process upsets would not violate the safe slab limit. The safe volume control on stack pellets and scrap pellets is subject to configuration control. Dropped pellets, if any, will essume a safe slab configuration. The fault tree in Figure 6.1-3 considers certain potential initiating events, none of which lead to criticality. These initiating events are discussed herein to demonstrate that they are very unlikely. Initial Issue Date:, 31 JUL 98 Page No. I1 l Revision Date: Revision No.,_0 L------_-------------_--------

IE-1. Not applicable o e IE-2. The roof, overhead pipes, e:c., provide integrity to prevent rources of moderator. Even if the integrity were lost, the moderator would affect only a small portion of the infinite slab. The slabs do not have the capability to hold a large quantity of moderator so i that the moderating effect ofinadvertent moderator would be quite small. IE-3 through IE-9. Not applicable or deleted IE-10. Use of water as a fire suppressant is limited to sprays or mists. This will provide a low density moderator over a small area of an infinite slab array, producing a small moderating effect on the assumed infinite slab. i IE-11. Administrative controls on nonfavorable geometry containers prevent the collection of i e moderator in nonfavorable geometry containers. Process equipment is not capable of collecting large quantities of moderator. Movable NFG containers are not permitted in the area per j COP-843002 and sketch 843002-3. Note: IE-11 was deleted from the fault tree because it is I outside the scope if this CSE. IE-12 & IE-13. Not applicable l 1 IE-14. The nylon spacer blocks are designed to support rods in a one-high array. Rods could be inadvertently stacked higher, but would be unstable. Sources of moderator are limited to those used in the process. There are no fluid system piping systems passing though or in the rod loading room, IE-15. The casket is limited administratively to five layers of fuel rods on nylon spacer blocks. e A sixth layer mig'.t fit into the box by operator error, het it may also interfere with placement of the top onto the box. IE-16. Caskets are administratively limited to a one-high stacking arrangement. The crane could be used to stack caskets. However, the number of caskets is limited and moderator l would have to be added to the caskets. This is not a credible scenario since the caskets must be closed when fully loaded.- One fully loaded casket would not be critical even if flooded with water. j IE-17. Two caskets, maximum, may be transported at any one time. This limit minimizes the e possibility of a casket falling off the forklift and spilling the contents. Criticality is not credible with the rods closely arrayed within two caskets in a side-by-side array. IE-18. Moderator for process operations (oils, solvents, mop water, etc.) is brought into the area in favorable volume or favorable geometry containers. e IE-19. Deleted Common Mode Failure Initial Issue Date: 31 JUL 98 Page No. 12 l. Revision Date: Revision No. _0 L lL_ _ _ __--_-

1 l No common mode failure potential has been identified for this evaluation. . Summary Tables - See Tables 5.3-3 and 5.3-4. l' - QC Inspection Area The IFBA fuel rods are processed with the same nuclear criticality safety limits and controls as are ADU fuel rods. One inspection process (the passive gamma scanner) is used only for IFBA fuel ) rods. With this exception, the Criticality Safety Evaluation for ADU rods in the QC Inspection ' Area is applicable to the QC inspection of IFBA fuel rods. Handling of fuel rods is such that, for nuclear criticality' safety purposes, ADU and IFBA fuel rods may be intermingled. For the evaluation of nuclear criticality safety limits and control, the user is referred to the CSE I for ADU Fuel Rod Manufacturing Area. Scrap / Rework ofIFBA fuel Rods i 1 Controls Safety Significant Controls i Passive Engineered Controls (PEC) a) The roof, overhead pipes, etc., provide integrity to pievent sourry s of moderator. IE-2. Periodic verification is no_t needed because any leaks are readily de%:ted and corrected during normal process operations. b) The fuel rod handling system processes rods in a one-high plane. IE-7. This IE postulates that this system somehow. fails, and allows fuel rods to achieve a depth of >4.5". Periodic verification is e needed because of continuous surveillance during fuel rod processing - operations. c) Fuel rods'are limited to a safe slab (favorable geometry) by the walls of the channels. Channels are transported cne at a time or on car... IE-8. Performance verification is no_t required. Ar built verification is required by configuration control when new channels are placed into service. d) Storage racks' at fuel rod scrap / rework maintain a depth of rods s 4.5". IE-9. This IE postulates that this passive engineered control somehow fails. Periodic verification is not p needed because of continuous surveillance during fuel rod processing operations. . betive Engineered Controls (AEC) - None 1 I Administrative Controls with Computer and/or Alarm Assist - None

Administrative Controir (AC)

Initial Issue Date: 31'.TUL 98 Page No. 13 l Revision Date: Revision No. 0

l a) Water as a fire suppressant is used as a spray or mist. IE-10. Periodic training of personnel in area is required. .b) Only one fuel rod may be out of a channel for each scrap workstation at any one time. IE-20. Continuous, periodic performance verification by operators and supervisors is required. ' Margin of Safety The' margin of safety is adequate, and also quite large, because the Bounding Conditions are much -more reactive than conditions expected for normal, and expected or credible upset conditions. Calculations assume full interstitial mderation and full water reflection. The calculations indicate that k,,for the normal and expected upset coaditions will not exceed 0.95. No credible upset will cause k,, to.>_1.0. The parameters that affect neutron multiplication, given the bounding assumptions, are geometry i and moderation. The controls on these parameters are both engineered and administrative in i nature. 1 Criticality would be possible only if fuel rods were phced in a large container of water or other moderator. The fuel rods would also have to exceed the boundaries of a safe slab. Since such containers are not available in the IFBA Area, such a scenario is not credible. The double contingency principle has been satisfied. Summary OfInitiating Events that lead to Credible Process Upsets No credible initiating events have been identified for this system that could lead to a criticality (k,, = 1.0). For moderation control, the plane of the safe. slab is well above the floor so that flooding is not j credible. Accidental (roof leaks) or deliberate (fire suppression) sources of moderator would be low density materials so that optimum moderation is not credible. For geometry control, credible j process upsets would not violate the safe slab limit. The safe volutae control on stack pellets and scrap pellets is subject to configuration control. Dropped pellets, if any, will assume a safe slab configuration. I The fault tree figure 6.3-2 (fuel rods) considers certain potential initiating events, none of which lead to ' criticalhy. These initiating events are discussed hereb to demonstrate that they are very unlikely. 1

• IE-1. Deleted
• IE-2. The roof, overhead pipes, etc., provide integrity to prevent sources of moderator.

Even if the integrity were lost, the moderator would affect only a small portion of the ~ infinite b Initial Issue Date: 31 JUL 98 Page No. 14 L Revision Date: Revision No. _0 i l E _ _ _ - _ = - _ - _ _ - - - _ - - - -. - - - _ _. -. _ _ _ _ - - - - - - -

slab. The slabs do not have the capability to hold a large quantity of moderator so that the modmaing effect of inadvertent moderator would be quite small. i .* IE,3 through IE-7. Not applicable or deleted j l IE-8. The fuel rod channels provide a favorable geometry container for fuel rods. Loss of e spacing or maintenance of a common plane for the channels would lend to loss of geometry. IE-9. Scrap / rework storage rack configuration prevents a depth of rods > 4.5". i IE-10. Use of water as a fire suppressant is limited to sprays or mists. This will provide a l e low density moderator over a small area of an infinite slab array, producing a small j moderating effect on the assumed infinite slab. IE-11. Administrative controls on nonfavorable geometry containers prevent the collection of moderator in nonfavorable geometry containers. Process equipment is not capable of collecting large quantities of moderator. Movable NFG containers are not permitted in the area per COP-843002 and sketch 843002-3. Note: IE-11 was deleted from the fault tree because it is outside the scope if this CSE. IE-12 tleough IE-17. Not applicable IE-18. Moderator for process operations (oils, solvents, mop water, etc.) is brought into the area in favorable volume or favorable geometry containers. ) IE-19. Good housekeeping prevents unwanted accumulations of pellets / rods to >4.5" depth. It also provides identification of SNM, minimizes combustibles and, hence, the possibility of introducing fire suppression water (moderator), and allows room to correctly space favorable geometry containers. IE-20. One fuel rod may be being scrapped or reworked at a station at one time. This is a limit that is easily controlled and easily provides geometry control. Criticality is not credible with one fuel rod. Common Mode Failure No cotamon mode failure potential has been identified for this evaluation. Summary Tables - See Tables 5.3-2 and 5.3-4.

l..

Initial Issue Date: 31 JUL 98 Page No. 15 Revision Date: Revision No. 0 _ =

Table 5.3-1

SUMMARY

OF DEFENSES AGAINST A SINGLE FAILURE IN THE IFBA PELLET DRYING AND ROD MANUFACTURING AREA (PELLETS) General Descriptor Defense Set 1 Defense Set 2 Prevent Regulate Detect / Prevent Regulate Detect React .w o m,, n ',y -- e a.; ~~, 2. ygnu p., - "' R:h.: . sa 'n. s no pd4. hb}kiQh(Y.., .lf: j cd g s.,.f;c, of ;-g , v. n ,g, s Pellets Exceeding 4.5" Slab 1, 7 12 19 Moderator Contingency Thickness ,f u,, s, ~ ). s, .m. ~

M' l;# I ;

5 4 '\\ q..+. Moderator Contingency) l' 3- .g s gg >r. v .;g +ys Full Interstitial Moderation Geometry Contingency 2, 6 10,18 19 l 4 f I i l i Initial Issue Dat:: 31 JUL 98 Page No. 16 Revision Date: Revision No. _0 L...

Table 5.3-2

SUMMARY

OF DEFENSES AGAINST A SINGLE FAILURE I IN THE IFBA PELLET DRYING AND ROD MANUFACTURING AREA (RODS) General Descriptor Defense Set 1 Defense Set 2 l l l .j Prevent Regulate Detect / Prevent Regulate Detect j React tyi %{f 3 c-W.' .... ^'.^y O; %c + i i#dy J' g,eiGeosnetryi C 'i + 7.- jyj ' > ' 4, J ~ ,, 4 33r <fJ ' '; n 3 9 Fuel Rods Exceeding 4.5" Slab 7,8,9,20 19 Moderator Contingency I Thickness i i ~.+:f T

s. - gn r ny;y.f.!-f ;~;Q '

~ Afi, :...

rgpyg}Q rYl' ysR.

l% l-z w cs; m y +.

s. s py y..

3.;4y, a~,.. c u ~g ("; m, w :ng.y;. n9;, :. o 5 %+ ' x. W_ :,' -:p y ) w~ 'o + .r..- eg p -g, :. 3 y j Full Interstitial Moderation Geometry Contingency 2, 6 10,18 ) i 1 ) 4 1 I 4 Initial Issue Date: 31 JUL 98 Page No. 17 l Revision Date: Revisian No. 0

Table 5.3-3

SUMMARY

OF DEFENSES AGAINST A SINGLE FAILURE IN THE IFBA PELLET DRYING AND ROD MANUFACTURING AREA (TRANSPORT RODS) General Descriptor Defense Set 1 Defen" r t 2 e Prevent Regulate Detect / Prevent Reguine Detect React g,4' 4;; s.., r-. m

s.,.,

.E;#l9.g; i f,tg.; <'., w >A. Geometryr.Contingen_... ;j ~ ';qp IN,j,*,, ' y/2, 3 g-{ hij -h;ji J :b.. '.. ~

y u

-~ cy" ' i ..Di M.7" -+ - 'y ' ' gj. ' tip%, M

• <4 ci v-7 g

Fuel Rods Exceeding 4.5" Slab 14, 15 16,17 Moderator Contingency Thickness Moderators _ Con]tingency r [K'

n > ' <7y ;, og. ],

, 8 ;y , :q, ,,, 5M,'., s s g< .s 1 w-1 Full Interstitial Moderation Geometry Contingency 2 10,18 Initial Issue Date: 31 JUL 98 Page No. 18 Revision Date: Revision No _0

Table 5.3-4 NUCLEAR CRITICALITY SAFETY LIMITS l FOR Korr = 0.90, 0.95, AND DELAYED CRITICAL tPARAMETER ' iNORMAL . LBOUNDINGi ... y;;b CRITICALIT1 CRITICALITY CRITICALITY) l (,.gf OPERATING . ASSUMPTIO : ' ,Y) SAFETY JLIMITK LCONDITION',

N

ISAFETY. LIMIT . Delayed Critleal

ddL w '.., y

.S.)

.kLIMITp i s 0.95 ; + + , s 0.90) l 2"U MASS Low Unrestricted N/A N/A N/A MODERATOR / Optiraum (Not (Not Optimum CONCENTRATION None Interstitial Determined) Determined) Interstitial Moderation Moderation One-High Pellets / Rods Pellets / rods GEOMETRY Pellet / Rod Infinite x-y N/A Stacked 4.1" Stacked 4.5" Planar Array Slab High High SPACING N/A N/A N/A N/A N/A Heterogeneous Heterogeneous Heterogeneous Heterogeneous Heterogeneous DENSITY / FORM UO, UO, UO UO UO 3 2 3 ABSORBERS N/A N/A N/A N/A N/A ENRICHMENT s 5.0 wt. % < 5.0 wt % s 5.0 wt. % s 5.0 wt. % s 5.0 wt. % Partial Water Partial Water Partial Water Partial Water Partial Water REFLECTION (1 inch) (1 inch) (1 inch) (1 inch) (1 inch) l l Initial Issue Date: 31 JUL 98 Page No. 19 Revision Date: Revision No. _0 i

l l FIGURE 6.3-1 FAULT TREE IFBA ROD MANUFACTURING AREA (PELLETS) SUFFICIENT HEIGHT OF UO2 PELLETS AND VOLUME OF MODERATOR CONTI ENCY ADDIflO-OF f Ut L IN T E FIS ilitAL ODE RA TK)N' I l IE 1 IE-7 IE-12 IE 19 F CONTI SMI CONTROL Pe t.t t Ts At PELLETS ACCUMULATE TO $4 5' DE P TH 34.5" DEPTH BY FAILURE OF Ft GOOD HOUSEKEEPING t q NOTE 5 MOP 750353 k TRAINING & WORK PRACTICE ANNUAL TRhNING & NOTE 3,5 WORK PRACTICE INVENTORY NOTE 2 lE-2 IE4 IE 18 IE-10 SMI CONTROL FULL INTERSTITIAL MODERATION FROM FALURE OF CONTROLS ON SOLUTIONS s-o ' *41$UEi"" 6 o -E. EP B-01 MOP-750353 NOTES:

1) IE-3. IE-4. IE-5. IE-0 AND IE 11 DELETED.

2) THAlNING AND WORK PRACTICE LIMIT TRAYS TO 1-HIGH. IT IS NOT CREDIBLE TO STACK PELLETS IN/ON CAPTURED ROW TRAYS.

3) CRITICALITY NOT CREDIBLE IN CASSETTES. SEE CSE SECTION 5.3.2 9.

4) lE-8 AND IE-13 THROUGH IE 17 NOT APPUCABLE.

5) IE4,IE-7 AND IE-12 APPLYONLY IN GLOVEBOX.

HO COMMON MODE FAILURE IDENTIFIED FOR MODERATOR AND LOSS OF GEOMETRY CONTROL. 1 Initial Issue Date: 31 JUL 98 Page No. 20 Revision Date: Revision No. _0

FIGURE 6.3-2 FAULT TREE IFBA ROD MANUFACTURING AREA (RODS)

1"!1aa?'^"a CONTI ENCY ADDt T10 OF F Ut L IN Tt HS TlI4Al Out.RA I BON' I

IE-7 IE4 IE-19 l l IE4 DEPTH A LUR OF GOOD HOUSEKEEPING PRACTICES t a 2 6 PEC MOP-750353 suunnamn k MOP-961210 l IE-2 l IE4 IE 18 IE-10 F Shit C@dTROL FULL INTERSTmAL OF R S S (OfL8, SOLVENTS, MOP WATER, ETC.) k NOTE 5 MOP-750353 EP 841 NOTES. ) (E IE-2 G 17 NOT APPLICABLE. HO COMMON MODE FALURE IDENTIFIED FOR MODERATOR AND LOSS OF GEOMETRY CONTROL Initial Issue Date: 31 JUL 98 Page No. 21 Revision Date: Revision No. O

FIGURE 6.3-3 FAULT TREE IFBA ROD MANUFACTURING AREA (ROD TRANSPORT) >4 5 INCHES OF RODS AND INTERSTITIAL MODERATOR a l IE 14 IE-15 IE-16 IE-17 l EE M O O MOP-871160 MOP-871160 MOP 471150 MOP-871150 IE 18 IE-10 E,E r SMICONTROL CONTI ENCY' 5 FULL INTERSTITIAL F Ut l IN T WS TI TIA L OM f A#L UHi MODERATION FROM F AILURE Moot A A Y no F Hou F iME m Mtu k OF CONTROLS ON SOLUTION! buPPHI isSION WA TE R (OfLS, SOLVENTS, MOP WATER, ETC.) 6 O EP B41 MOP 750353 NOTES:

1) IE-1. lE4. lE-7. lE-8. lE-12. lE-13. AN0 lE-19 NOT APPLICABLE.

2) IE-3,IE4,IE-5,lE4 AND IE-11 DELETED.

'NO COMMON MODE FAILURE IDENTIFIED FOR MODERATOR AND LOSS OF GEOMETRY CONTROL. Initial Issue Date: 31 JUL 98 Page No. 22 Revision Date: Revision No. _0

Chemical Safety and Fire Safety Controls l To be provided in a future Integrated Safety Assessment. 1 I l i. i t Initial hsue Date: 31 JUL 98 - Page No. 23 Revision Date: Revision No. _0 _}}